https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107937
--- Comment #6 from Martin Liška <marxin at gcc dot gnu.org> --- Another test-case: $ cat warn.i int regs, vm_debug_engine_vp_0, vm_debug_engine_vp_2; void vm_dispatch_hook(); void vm_debug_engine() { int fp; void *jump_table = &&l_nop; l_nop: if (__builtin_expect(vm_debug_engine_vp_2, 0)) vm_dispatch_hook(); if (_setjmp(regs)) { fp = fp; vm_dispatch_hook(); goto *jump_table; } vm_debug_engine_vp_0 = fp; } $ gcc -c warn.i -O1 -Wall warn.i: In function ‘vm_debug_engine’: warn.i:14:7: warning: implicit declaration of function ‘_setjmp’ [-Wimplicit-function-declaration] 14 | if (_setjmp(regs)) { | ^~~~~~~ during GIMPLE pass: uninit warn.i:8:1: internal compiler error: in find_var_cmp_const, at gimple-predicate-analysis.cc:257 8 | vm_debug_engine() { | ^~~~~~~~~~~~~~~ 0x84abb6 find_var_cmp_const /home/marxin/Programming/gcc/gcc/gimple-predicate-analysis.cc:257 0x1c83ff2 uninit_analysis::overlap(gphi*, unsigned int, hash_set<gphi*, false, default_hash_traits<gphi*> >*, predicate const&) /home/marxin/Programming/gcc/gcc/gimple-predicate-analysis.cc:648 0x1c83b45 uninit_analysis::is_use_guarded(gimple*, basic_block_def*, gphi*, unsigned int, hash_set<gphi*, false, default_hash_traits<gphi*> >*) /home/marxin/Programming/gcc/gcc/gimple-predicate-analysis.cc:2215 0x1c840ea uninit_analysis::is_use_guarded(gimple*, basic_block_def*, gphi*, unsigned int) /home/marxin/Programming/gcc/gcc/gimple-predicate-analysis.cc:2249 0x11188e7 find_uninit_use /home/marxin/Programming/gcc/gcc/tree-ssa-uninit.cc:1234 0x111923e warn_uninitialized_phi /home/marxin/Programming/gcc/gcc/tree-ssa-uninit.cc:1304 0x111923e execute_late_warn_uninitialized /home/marxin/Programming/gcc/gcc/tree-ssa-uninit.cc:1425 0x111923e execute /home/marxin/Programming/gcc/gcc/tree-ssa-uninit.cc:1442 Please submit a full bug report, with preprocessed source (by using -freport-bug). Please include the complete backtrace with any bug report. See <https://gcc.gnu.org/bugs/> for instructions.